1. Field of the Invention
The present invention relates to a system, method, and program for simulating Input/Output (I/O) requests to test a system.
2. Description of the Related Art
Computing systems often include one or more host computers (“hosts”) for processing data and —running application programs, direct access storage devices (DASDs) for storing data, and a storage controller for controlling the transfer of data between the hosts and the DASD. Storage controllers, also referred to as control units or storage directors or servers, manage access to a storage space comprised of numerous hard disk drives connected in a loop architecture, otherwise referred to as a Direct Access Storage Device (DASD). Hosts may communicate Input/Output (I/O) requests to the storage space through the storage controller.
As part of the manufacturing process, the storage controller is stress and load tested before shipment to the customer. This test process requires that the storage controller be connected in an actual operating environment, which would include multiple host systems, switches, etc., and that the host systems would transmit I/O requests to the storage controller to stress and load test the storage controller's capability to handle the I/O load. This testing process is quite burdensome and expensive because the manufacturer must maintain and operate host systems capable of generating I/Os at a rate commensurate with the intended operating environment. Further, significant human labor is required to connect and disconnect host systems to the multiple I/O ports on each storage controller being tested for shipment. These labor costs are substantial when numerous storage controllers are being shipped. Further, a large warehouse floor space may be needed for the host systems and storage controllers being tested.
Moreover, as the number of I/O attachment ports in a storage controller increases, additional host systems, switches, and human labor are needed to connect to the increased number of I/O ports on the storage controller in order to stress and load test the additional ports.
For these reasons, there is a need in the art for improved and more cost effective techniques to stress and load test storage controllers and other I/O devices that are intended to interface with numerous connected devices that transmit I/O.